diff --git a/.github/workflows/presubmit.yaml b/.github/workflows/presubmit.yaml
index 9c37deef21d..2cfb65ad4b2 100644
--- a/.github/workflows/presubmit.yaml
+++ b/.github/workflows/presubmit.yaml
@@ -18,6 +18,7 @@ jobs:
       - uses: pnpm/action-setup@v4
         with:
           version: ^10.0.0
+      - uses: oven-sh/setup-bun@v2
       - run: node --version
       - run: ci/run_conditional_tests.sh
         name: Run unit tests
diff --git a/.github/workflows/windows-presubmit.yaml b/.github/workflows/windows-presubmit.yaml
index 624c0f32a7c..8795e6362d3 100644
--- a/.github/workflows/windows-presubmit.yaml
+++ b/.github/workflows/windows-presubmit.yaml
@@ -11,6 +11,13 @@ jobs:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 300
+      - name: Update Windows path to use Linux/MacOS compatible binaries from Git Bash
+        run: echo "C:\Program Files\Git\usr\bin" >> $GITHUB_PATH
+        shell: bash
+      - name: Check which cp is being used
+        run: where cp
+        run: echo %PATH%
+        shell: cmd
       - name: Use Node.js ${{ matrix.node-version }}
         uses: actions/setup-node@v6
         with:
@@ -18,6 +25,7 @@ jobs:
       - uses: pnpm/action-setup@v4
         with:
           version: ^10.0.0
+      - uses: oven-sh/setup-bun@v2
       - run: node --version
       - run: bash ci/run_conditional_tests.sh
         name: Run windows unit tests
@@ -25,3 +33,6 @@ jobs:
         env:
           BUILD_TYPE: presubmit
           TEST_TYPE: units
+          SHELL: C:\Program Files\Git\bin\bash.exe
+          npm_config_script_shell: bash
+
diff --git a/ci/run_conditional_tests.sh b/ci/run_conditional_tests.sh
index a7902ed6ca9..3e962d0e476 100755
--- a/ci/run_conditional_tests.sh
+++ b/ci/run_conditional_tests.sh
@@ -61,11 +61,11 @@ set -e
 if [[ "${changed}" -eq 0 ]]; then
     echo "no change detected in ci"
 else
-    echo "skipping trigger of tests for now: tracking in #7540"
-    # echo "change detected in ci, we should test everything"
-    # echo "result of git diff ${GIT_DIFF_ARG} ci:"
-    # git diff ${GIT_DIFF_ARG} ci
-    # GIT_DIFF_ARG=""
+    #echo "skipping trigger of tests for now: tracking in #7540"
+    echo "change detected in ci, we should test everything"
+    echo "result of git diff ${GIT_DIFF_ARG} ci:"
+    git diff ${GIT_DIFF_ARG} ci
+    GIT_DIFF_ARG=""
 fi
 
 # Now we have a fixed list, but we can change it to autodetect if
diff --git a/ci/run_single_test.sh b/ci/run_single_test.sh
index 31ce0206111..d1ab68a38f7 100755
--- a/ci/run_single_test.sh
+++ b/ci/run_single_test.sh
@@ -40,8 +40,13 @@ if [ ${BUILD_TYPE} != "presubmit" ]; then
 fi
 
 # Install dependencies
-echo "pnpm install --ignore-scripts --engine-strict --prod; pnpm install"
-pnpm install --ignore-scripts --engine-strict --prod; pnpm install
+#
+# The filter is needed to prevent bun from installing all packages in the repo
+# from the root. By default it prefers to analyze, install, and at the root
+# so dependencies can be deduplicated. We will try that in a separate PR for
+# comparison.
+echo "bun install --ignore-scripts --prod --filter .; bun install --filter ."
+bun install --ignore-scripts --prod --filter . ; bun install --filter .
 
 
 retval=0
@@ -49,20 +54,20 @@ retval=0
 set +e
 case ${TEST_TYPE} in
 lint)
-    pnpm prelint
-    pnpm lint
+    npm run prelint
+    npm run lint
     retval=$?
     ;;
 samples)
-    pnpm samples-test
+    npm run samples-test
     retval=$?
     ;;
 system)
-    pnpm system-test
+    npm run system-test
     retval=$?
     ;;
 units)
-    pnpm test
+    npm run test
     retval=$?
     ;;
 *)